


Good Boy

by SpectrumArcadia



Category: Haikyuu!!
Genre: Knotting, M/M, Other, Praise Kink, and a bit of, dogshifter Kyoutani Kentarou, pseudo-beastiality
Language: English
Status: Completed
Published: 2017-06-10
Updated: 2017-06-10
Packaged: 2018-11-12 11:04:28
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,034
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11160564
Author URL: https://archiveofourown.org/users/SpectrumArcadia/pseuds/SpectrumArcadia
Summary: "I've always wanted to knot you."Upon reflection, he should have thought longer and harder about his answer because his boyfriend immediately shuts him down."Absolutely not." The other laughs, as if Kyoutani's desire was ridiculous. Kyoutani frowns, opens his mouth only to be cut off with another amused snort. "Hell no."





	Good Boy

**Author's Note:**

> Prompt: Iwaizumi and/or Kyoutani is an animal shifter and can turn into a dog (can be as innocent or filthy as you like but weird shifter sex is definitely encouraged ;D). Done for SASO 2017~

 

"Absolutely not." Had been Iwaizumi's answer at the time. Followed by a fond "Hell no." and finally "I don't even think it will fit?"

 

Really, Kyoutani blames his big stupid mouth for asking the question and Iwaizumi's big, stupid, trustable, curious face for constantly coaxing the truth out of him. The alcohol probably didn't help either.

Seated on the porch of their shared abode, they had passed a beer back and forth for about 2 hours, just talking. Every time the bottle emptied it was replaced, keeping the talks going until both of them were a little more than comfortably inebriated.

 

It was Iwaizumi's fault, really. Things usually are.

"So what have you always wanted to try in the bedroom?" A sly grin accompanies a nudge to Kyoutani's shoulder and he considers it briefly before opening his mouth.

"I've always wanted to knot you."

Upon reflection, he should have thought longer and harder about the question because his boyfriend immediately shuts him down.

"Absolutely not." The other laughs, as if Kyoutani's desire was ridiculous. Kyoutani frowns, opens his mouth only to be cut off with another amused snort. "Hell no." Iwaizumi shakes his head, smiling, before furrowing his brows as if imagining it. "I don't even think it would fit? I mean- you make a pretty big dog."

Iwaizumi brings a hand up to his face, clenching into a fist and inspecting it. When it finally dawns on Kyoutani what he's comparing it to, he chugs the rest of the last beer, face beet red. Liquid courage burns through his veins and allows him to respond with a straight face.

"It would fit. Eventually. Lemme fist you."

 

The surprised look on Iwaizumi's face is worth everything.

 

\--

 

It takes nearly an hour, but when he finally has Iwaizumi shaking and clenching around his wrist, his boyfriend comes so spectacularly he manages to streak his own face. Kyoutani licks it clean for him before he is gently batted away.

"We can try it." Iwaizumi mumbles afterwards, a boneless heap in Kyoutani's arms. Kyoutani tilts his head in confusion before the air rushes from his lungs all at once in an embarrassing wheeze.

 

"Awesome." He manages, feeling the phantom sensation of his tail wagging.

 

\--

 

It was one thing fantasizing about it. Of course he thinks about sex with Iwaizumi in dog-form, he would think about sex with Iwaizumi in any form. And it was also curiosity as much as anything- things just felt different as a dog, his instincts stronger, his senses heightened. Sex would probably feel fantastic.

 

It was another thing altogether to have the reality of Iwaizumi dropping down to the floor, ass presented high in the air, thick thighs trembling ever so slightly. Kyoutani's cock is hard and dripping before he even knows it. Iwaizumi was right, he is a pretty big dog. Big enough to make his muscular boyfriend look almost small. It'll be easy to cover his body with this form, paws on the floor near his shoulders, cock thrusting wildly.

His haunches shift as he thinks about it, an involuntary thrusting motion and the dogshifter realizes that holding back is going to be harder than he thought. His canine body runs on instinct, he mostly lets it do what it wants. And right now he wants- _needs_ to mount his boyfriend, rub his slick red cock between Iwaizumi's round cheeks until the other helps guide him in.

Iwaizumi tremors ever so slightly in anticipation. Ass stretched and prepped already, he lets out a frustrated whine when Kyoutani just stares.

 

"You gonna mount me or what?" Iwaizumi growls. It's a challenge, accompanied by two of Iwaizumi's thick fingers reaching back and slipping inside of himself in a lewd wet glide. Kyoutani's now fully unsheathed cock drips down to the floor as he steps forward, covering Iwaizumi's body with his own.

As soon as the tip of his cock rubs his boyfriend's cheeks, Kyoutani cant help but thrust forward, cock slipping between them and rubbing wetly against his boyfriend's lower back. His hips move in small thrusts, he can barely keep it together.

"Watch it-" Iwaizumi groans, reaching back to take Kyoutani's thick cock into his hand. Guiding it to the right spot, Iwaizumi rubs the tip against his ass, groaning as it breaches him gently several times.

"Come on- that's good- be a good boy and fuck me-" He pants.

 

Kyoutani's hips snap and he bottoms out in one go, knocking the breath from Iwaizumi's lungs as he shouts.

He can't even think about stopping now, adjusting his position only slightly as he establishes a rough pace. Large ears swivel slightly to pick up the wet sounds of Iwaizumi's ass being fucked open by his loyal dog's prick. It feels amazing.

He trembles as his knot begins to swell, catching ever so slightly on Iwaizumi's hole. He slams in deep.

 

For a moment, a small lucid part of Kyoutani's mind panics. He doesn't remember what Iwaizumi had decided about the actual knotting part, did they agree to work up to that? Should he have pulled out?!

But it's too late now, Kyoutani's cock is swelling, tightening, and then-

They're locked together.

 

Kyoutani's orgasm hits him hard, a runny flood of cum rushing into Iwaizumi's ass, long burst after burst. Iwaizumi yells, and tightens up, shaking violently as he comes around Kyoutani's knot, milking him dry.

Harsh pants echo through the room as Kyoutani keeps pumping his boyfriend full and Iwaizumi tries to breathe as his guts slowly fill. After a moment, the dogshifter moves, lifting a leg and attempting to turn into a more comfortable breeding position. He is stopped by Iwaizumi's hands clamping down on his haunches.

"Don't you- fucking dare-" Iwaizumi pants, sounding positively wrecked. "I'm not some- bitch in heat- so you just- chill-" He groans, face pressed against the rug.

If Kyoutani could speak, he would argue that the tail to tail position would be more comfortable for both of them, but he settles on licking the sweat off the back of Iwaizumi's neck.

 

"I love you- you nasty shit-" He could hear the grin in Iwaizumi's voice. "Good boy."

 

Iwaizumi laughs as he feels Kyoutani's tail wag.

 


End file.
